JP2004133475A - Drive device of plasma display panel and driving method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive device of plasma display panel and a driving method thereof capable of adjusting rising time and falling time of a panel voltage separately. <P>SOLUTION: In a plasma display panel, an inductor is electrically connected to a Y-electrode of a panel capacitor. A current of a first direction is injected into the inductor, energy is reserved and, thereafter, the voltage of the Y-electrode is changed to a voltage V<SB>S</SB>/2 by using the resonance between the inductor and the panel capacitor and the reserved energy. A sustainment discharge is caused on the panel by a difference between the voltage V<SB>S</SB>/2 of the Y-electrode and a voltage -V<SB>S</SB>/2 of X-electrode. Then, a current of a second direction opposite to the first direction is injected to the inductor and the energy is reserved. By using the resonance between the inductor and the panel capacitor and the reserved energy, the voltage of the Y-electrode is changed to the voltage -V<SB>S</SB>/2. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a driving apparatus and a driving method for a plasma display panel.

2. Description of the Related Art A plasma display panel is a flat display device that displays characters or images using plasma generated by a gas discharge. Depending on its size, several tens to several million or more pixels are arranged in a matrix. I have. Such a plasma display panel is classified into a DC type and an AC type according to the form of a driving voltage waveform applied and the structure of a discharge cell.

In DC plasma display panels, the electrodes are exposed while the discharge space is not insulated, and the current flows through the discharge space as long as the voltage is applied. The disadvantage is that you have to make it. On the other hand, AC plasma display panels have the advantage that the electrodes are covered with a dielectric layer and the current is limited and stabilized by forming a series capacitance component, and the electrodes are protected from ion bombardment during discharge. And has a long service life.

(4) An AC type plasma display panel has a scanning electrode and a sustain electrode arranged in parallel with each other, and an address electrode is formed in a direction orthogonal to these electrodes. The sustain electrode is formed corresponding to each scanning electrode, and the sustain electrode is formed integrally with the adjacent sustain electrode at one end.

Generally, the driving method of an AC plasma display panel is expressed as a change in operation with time, and includes a reset period, an addressing period, a sustain discharge period, and an erase period.

The reset period is a period for initializing the state of each cell so that a smooth addressing operation to a discharge cell (hereinafter abbreviated as a cell) can be performed. The addressing period selects a lit cell and a non-lit cell on the panel. In order to perform the memory operation to apply an address panel and a scanning pulse to the electrodes passing through the lighting cell (addressing cell) to discharge, leaving wall charges on the dielectric layer etc. to facilitate the discharge for light emission is there. The sustain discharge period is a period in which a discharge for actually displaying an image is performed on a cell addressed by applying a sustain discharge pulse, and the pulse is repeated by the number of times proportional to a desired luminance. The erase period is a period in which the wall discharge of the cell is reduced to end the sustain discharge.

At this time, the discharge space and the like between the scan electrode and the sustain electrode and between the surface on which the address electrode is formed and the surface on which the scan and sustain electrode is formed are referred to as a capacitive load (hereinafter referred to as a "panel capacitor"). ), A capacitance component exists in the panel. Therefore, in order to apply a voltage waveform for frequent sustain discharge, a large amount of reactive power is required for charging and discharging the capacitance. Since this reactive power imposes a heavy burden on the power supply circuit, a power recovery circuit that recovers and reuses the reactive power is incorporated in the drive circuit of the plasma display panel to reduce the burden. As such a power recovery circuit, L.A. F. There is a circuit proposed by Weber (for example, see Patent Documents 1 and 2).

The Weber circuit uses the resonance between the panel capacitor and the inductor to transfer the energy of the panel to the power recovery capacitor, or to repeat the operation of transferring the energy stored in the power recovery capacitor to the panel, thereby producing a reactive power. Collect. However, in the Weber circuit, the rise and fall times of the panel voltage are determined by the time constant (LC) based on the inductance (L) of the inductor and the capacitance (C) of the panel capacitor. However, since the time constant (LC) in the Weber circuit is always constant, the rise time and the fall time of the panel voltage become the same. For example, in order to increase the rise time of the panel voltage, the switching element connected to the power supply must be hard-switched during the rise of the panel voltage, so that the stress of the switching element increases. In addition, power loss occurs due to hard switching, and the adverse effect of EMI (electromagnetic interference) increases.

U.S. Pat. No. 4,866,349 U.S. Pat. No. 5,081,400

The present invention has been made in view of such a problem, and an object of the present invention is to provide a driving apparatus and a driving method of a plasma display panel capable of adjusting a rise time and a fall time of a panel voltage independently of each other. To provide.

According to the present invention, there is provided a method and apparatus for driving a plasma display panel in which a panel capacitor is formed between first and second electrodes.

According to the method for driving a plasma display panel according to the first aspect of the present invention, first, while the voltages of the first and second electrodes are each maintained at the first voltage, an inductor is electrically connected to the first electrode. A current in a first direction is injected into the inductor to store first energy (first stage). Then, after changing the voltage of the first electrode to the second voltage using the resonance between the inductor and the panel capacitor and the first energy (second step), the energy remaining in the inductor is recovered (third step). ). According to this configuration, by adjusting the time for injecting the current in the first direction into the inductor, the rise time of the panel voltage, which is the voltage across the panel capacitor, can be adjusted. By adjusting the time during which the current is injected, the fall time of the panel voltage can be adjusted. At this time, it is preferable that the amount of current injected into the inductor in the first direction is larger than the amount of current injected into the inductor in the second direction. In this case, the rise time of the panel voltage can be shortened and the fall time can be lengthened.

Further, in the method according to the first aspect, while maintaining the voltages of the first and second electrodes at the second and first voltages, respectively, the second direction which is opposite to the first direction is applied to the inductor. A second step of injecting a current and storing the second energy; and maintaining the second energy and the resonance between the inductor and the panel capacitor while the voltage of the second electrode is maintained at the first voltage. A fifth step of changing the voltage of the first electrode to the first voltage by using the first and second voltages, and an energy remaining in the inductor while maintaining the voltages of the first and second electrodes at the first voltage, respectively. And a sixth step of collecting the data. In the method according to the first aspect, the difference between the first voltage and the second voltage is preferably a sustain discharge voltage.

Also, the first and second voltages in the method according to the first aspect are supplied by first and second signal lines, respectively, and the first step includes a third step having a magnitude between the first and second voltages. Injecting the current in the first direction into the inductor through a path formed by a third signal line for supplying a voltage, the inductor, and the first signal line; The current in the second direction may be injected into the inductor through a path formed between the inductor and the third signal line.

The second step in the method according to the first aspect may include generating resonance in a path formed between the third signal line, the inductor, and the panel capacitor, and the fifth step includes generating the resonance in the panel capacitor and the inductor. And resonance may be generated in a path formed in the third signal line, and a voltage difference between a third voltage, which is a voltage between the first voltage and the second voltage, and a voltage of the first electrode. May cause resonance.

The third voltage in the method according to the first aspect is provided by a capacitor, the current in the first direction is a current discharged from the capacitor, and the current in the second direction is a current charging the capacitor. Yes, the energy discharged from the capacitor and the energy for charging the capacitor may be substantially the same. The third voltage may be a voltage intermediate between the first voltage and the second voltage, and the third voltage may be a voltage intermediate between the first voltage and the second voltage. And the second voltage. The third voltage is supplied by a capacitor, the current in the first direction is a current discharged from the capacitor, and the current in the second direction is a current for charging the capacitor, and is discharged from the capacitor. The energy to be charged may be smaller than the energy to charge the capacitor.

According to the driving method of the plasma display panel according to the second aspect of the present invention, first, the first inductor and the panel capacitor electrically connected to the first electrode while maintaining the voltage of the second electrode at the first voltage. The voltage of the first electrode is changed to the second voltage by using the resonance during the eleventh period (step 11), and the voltages of the first and second electrodes are maintained at the second and first voltages, respectively (step 12). Next, the voltage of the first electrode is changed to the first voltage using the resonance between the second inductor electrically connected to the first electrode and the panel capacitor (step 13), and the first and second voltages are changed. Each electrode voltage is maintained at the first voltage (step 14). According to this configuration, the rise time and the fall time of the panel voltage, which is the voltage across the panel capacitor, are functions of the inductances of the first inductor and the second inductor, respectively. The rise time and fall time can be adjusted. At this time, it is preferable that the first inductor has a smaller inductance than the second inductor. In this case, the rise time of the panel voltage can be shortened and the fall time can be lengthened. Preferably, the difference between the first voltage and the second voltage is a sustain discharge voltage.

An eleventh step of the method according to the second aspect is a path formed in the signal line for supplying a third voltage having a magnitude between the first and second voltages, the first inductor, and the panel capacitor. In the thirteenth step, the resonance may be generated in a path formed in the panel capacitor, the second inductor, and the signal line.

The driving apparatus of the plasma display panel according to the third aspect of the present invention includes an inductor electrically connected to the first electrode. While the voltages of the first and second electrodes are each maintained at the first voltage, a signal line for supplying a third voltage having a magnitude between the first and second voltages, an inductor, and a second for supplying the first voltage. A first path is formed in one power supply, and a current in a first direction is injected into the inductor. While the current in the first direction is flowing through the inductor, LC resonance is generated by the second path formed in the signal line, the inductor, and the panel capacitor, and the voltage of the first electrode is changed from the first voltage to the second voltage. You. While the voltages of the first and second electrodes are maintained at the second and first voltages, respectively, a third path is formed in the second power supply for supplying the second voltage, the inductor, and the signal line, and the first path is formed in the inductor. A current is injected in a second direction opposite to the direction. While the current in the second direction flows through the inductor, LC resonance occurs due to the fourth path formed in the panel capacitor, the inductor, and the signal line, and the voltage of the first electrode is changed from the second voltage to the first voltage. You. By adjusting the time for injecting the current in the first direction, the rise time of the panel voltage, which is the voltage across the panel capacitor, can be adjusted. Similarly, the time for injecting the current in the second direction into the inductor can be adjusted. By doing so, the fall time of the panel voltage can be adjusted. At this time, it is preferable that the amount of current injected into the inductor in the first direction is larger than the amount of current injected into the inductor in the second direction. In this case, the rise time of the panel voltage can be shortened and the fall time can be lengthened. Preferably, the difference between the first voltage and the second voltage is a sustain discharge voltage.

The device according to the third aspect may further include a capacitor for charging a third voltage. The third voltage may be a voltage intermediate between the first voltage and the second voltage, and the third voltage may be a voltage intermediate between the first voltage and the second voltage and the third voltage. It may be a voltage between two voltages.

In the apparatus according to the third aspect, the energy discharged from the capacitor by the current in the first direction is substantially the same as the energy charged to the capacitor by the current in the second direction. May be. In this case, the energy discharged from the capacitor by the current in the first direction may be smaller than the energy charged to the capacitor by the current in the second direction.

Also, in the apparatus according to the third aspect, after the voltage of the first electrode is changed to the second voltage, the first electrode is electrically connected to the second power supply to thereby change the voltage of the first electrode. May be further included in a fifth path for maintaining the voltage at the second voltage.

Further, in the device according to the third aspect, after the voltage of the first electrode is changed to the second voltage, the current in the first direction, which is formed in the inductor and the second power supply and flows through the inductor, A sixth path for collecting, and a seventh path formed on the inductor and the signal line after the voltage of the first electrode is changed to the first voltage and collecting the current in the second direction flowing through the inductor. May be further included. The second electrode may be electrically connected to the first power supply and maintained at the first voltage.

Also, in the apparatus according to the third aspect, a first switching element connected between the first power supply and the first electrode, and a second switching element connected between the second power supply and the first electrode. A second switching element, and third and fourth switching elements connected in parallel between the inductor and the signal line, wherein the first path turns on the first and third switching elements, and , The second path is formed by turning off the second and fourth switching elements, and the second path is formed by turning on the third switching element and turning off the first, second, and fourth switching elements. The three paths are formed by turning on the second and fourth switching elements and turning off the first and third switching elements, Serial fourth path, turn-on of the fourth switching element, and, may be formed by turning off of the first to third switching elements.

Also, in the device according to the third aspect, the first voltage may have the same magnitude as the second voltage and opposite signs, and the signal line may be connected to a ground line. The first voltage is a ground voltage, the third voltage is a voltage corresponding to half of the second voltage, and the signal line is connected to a capacitor charging the third voltage. Is also good.

A driving apparatus of a plasma display panel according to a fourth aspect of the present invention includes a first and a second inductor electrically connected to the first electrode, respectively, and a state in which the voltage of the second electrode is maintained at the first voltage. Then, a resonance occurs between the first inductor and the panel capacitor to change the voltage of the first electrode to a second voltage, and the voltage of the second electrode is changed to the first voltage. And a second resonance path in which resonance occurs between the second inductor and the panel capacitor while the voltage of the first electrode is changed to the first voltage. In this case, it is preferable that the first inductor has a smaller inductance than the second inductor.

The method of driving a plasma display panel according to a fifth aspect of the present invention includes charging the panel capacitor from a twelfth voltage to a thirteenth voltage while the voltage of the second electrode is maintained at an eleventh voltage. Discharging the panel capacitor from the thirteenth voltage to the twelfth voltage while maintaining the voltage of the second electrode at the first voltage. At this time, it is preferable that the time for charging the panel capacitor is shorter than the time for discharging the panel capacitor.

A method of driving a plasma display panel according to a sixth aspect of the present invention includes the steps of: storing first energy in an inductor electrically connected between a capacitor charging a predetermined voltage and the panel capacitor; Charging the panel capacitor through the inductor in which the first energy is stored, storing the second energy in the inductor, and discharging the panel capacitor through the inductor in which the second energy is stored. including. At this time, it is preferable that the predetermined voltage is adjusted according to the amounts of the first energy and the second energy.

As described above, according to the present invention, it is possible to provide a driving apparatus and a driving method of a plasma display panel capable of adjusting a rising time and a falling time of a panel voltage independently of each other.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted.

First, a plasma display panel applicable to first to fourth embodiments to be described later of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic block diagram of a plasma display panel according to the present embodiment.

As shown in FIG. 1, the plasma display panel according to the present embodiment includes a plasma panel 100, an address driver 200, a scan / sustain driver 300, and a controller 400.

In FIG. 1, a plasma panel 100 has a plurality of address electrodes A1 to Am long in a column (vertical) direction and arranged in parallel with each other, and a first electrode long in a row (horizontal) direction and arranged in parallel with each other. A plurality of scan electrodes Y1 to Yn (hereinafter, referred to as Y electrodes), and second electrodes, for example, sustain electrodes (X1 to Xn) (hereinafter, referred to as X electrodes) arranged in parallel one by one corresponding to each Y electrode. )including. The X electrodes X1 to Xn generally have one end connected to an adjacent X electrode and have a finger shape as a whole. The control unit 400 receives an external video signal, generates an address driving control signal and a sustain discharge control signal, and applies them to the address driving unit 200 and the scan / sustain driving unit 300, respectively.

The address driver 200 receives the address driving control signal from the controller 400 and applies an address pulse for selecting a discharge cell to be displayed to each address electrode. The scan / sustain driver 300 receives a scan control signal and a sustain discharge control signal from the controller 400, outputs a scan pulse to the Y electrode, selects a cell to be turned on, stores a discharge preparation state, and then performs a sustain discharge. Upon receiving the control signal, a sustain discharge pulse is output to the Y electrode and the X electrode. The sustain discharge pulse is of an AC type in which the polarity between the X and Y electrodes is inverted each time, and a sustain discharge occurs in the discharge cell selected by this pulse.

Hereinafter, a sustain discharge circuit of the scan / sustain driver 300 according to the first embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 2 is a schematic circuit diagram of the sustain discharge circuit according to the first embodiment. FIG. 3 is a drive timing diagram of the sustain discharge circuit according to the first embodiment, and FIGS. 4A to 4H are circuit diagrams showing current paths in each mode in the sustain discharge circuit according to the first embodiment.

As shown in FIG. 2, the sustain discharge circuit according to the first embodiment of the present invention includes a Y electrode driver 310, an X electrode driver 320, a Y electrode power recovery unit 330, and an X electrode power recovery unit 340. Prepare. The sustain discharge circuit is basically symmetrical on the left and right (Y, X).

The sustain discharge circuit is connected to three external terminals (+ half-VS potential point, ground point, and -half-Vs potential point), respectively, and applies the second voltage, the third voltage, and the first voltage (eleventh voltage), respectively. It is composed of three lines (+ power line, ground line, and − power line) of a second signal line, a third signal line, and a first signal line to be supplied, and components connected therebetween. Y electrode driver 310 and X electrode driver 320 is coupled to the Y and X electrodes are opposite ends of panel capacitor C _p. Y electrode driver 310 includes a switching element _Y s, _{Y g,} X electrode driver 320 includes a switching element _X s, _{X g.} Y electrode power recovery unit 330 includes an inductor _{L 1} and the switching element _Y r, _{Y f,} the X electrode power recovery unit 340 includes an inductor _{L 2} and the switching element _X r, _{X f.} The switching element _{Y s, Y g, X s} , X g, Y r, Y f, X r, X f is preferably configured in a MOSFET having a body diode, satisfies the functions described below Other switching elements may be used as long as they are used. Incidentally, for example, the _Y g, _{Y s} constitute a first, one example of the second switching element, respectively, the _Y r, _{Y f} each third, constitute one example of a fourth switching element.

Switching element _Y s, _{Y g,} the power supplies the second voltage, for example, _V s / 2 voltage Vs / 2 (+ power supply line) and for supplying a first voltage, for example, _-V s / 2 voltage power source -Vs / 2 ( - are connected in series between the power supply line), the connection point of the Y _s and Y _g is connected to the Y electrode of the panel capacitor C _p (Vy in Figure). Similarly, the switching elements _X s, _{X g} is also power Vs / 2 and are connected in series between the power source -Vs / 2, _{X s} and _{X g} connection point panel capacitor _{C p} in the X electrode (figure Vx ).

The Y electrode of the panel capacitor C _p is connected to one end of the inductor L _1, the inductor L ₁ of the other end and the third voltage (here, for example, voltage 0) to the signal line (third signal line) for example, ground Switching elements Y _r and Y _f are connected in parallel with the line 0. Similarly, the X electrode of panel capacitor C _p is connected to one end of the inductor L _2, between the other end of the inductor L ₂ and the ground line 0 is connected in parallel switching elements X _r, X _f ing. The Y electrode power recovery unit 330 may further include diodes D _y1 and D _y2 for preventing a current path formed by the body diodes of the switching elements Y _r and Y _f . Similarly, the X electrode power recovery unit 340 further includes a diode _{D x1, D x2,} it is possible to prevent a current path that can be produced by the body diode of switch _X r, _{X f.} Also, the Y electrode power recovery unit 330 and the X electrode power recovery unit 340 clamp each other so that the other end voltages of the inductors L ₁ and L ₂ do not become larger than V _s / 2 or become smaller than −V _s / 2. For example, a diode (not shown) may be further included.

Next, a time-series operation change of the sustain discharge circuit according to the first embodiment of the present invention will be described with reference to FIGS. 3, 4A to 4H. Here, the operation change makes one cycle in the 16 modes M1 to M16, and the mode change is caused by the operation of the switching element. Further, a phenomenon referred to as LC resonance is not a continuous oscillation, voltage and in combination with the switching element _{Y r,} Y f, occurs during conduction of _{X r} or _{X f,} an inductor _{L 1} or _{L 2} and panel capacitor _{C p} This is a change phenomenon of current.

Before performing the operation according to the first embodiment of the present invention, the switching element _Y g, _{X g} is conductive, the panel capacitor _{C p} Y electrode voltage _{V y} and the X electrode voltage _{V x} are each -V _s / 2 Is maintained. Then, it is assumed that the capacitance of the panel capacitor _{C p} C, the inductance of the inductor _L 1, _{L 2} respectively and _L 1, _{L 2.}

As shown in FIG. 3 and FIG. 4A, when mode 1 (M1: an example of the first stage) starts, the switching elements _Yg and _Xg are on and the switching element _Yr is on. In Then the mode 1 (M1), the current in inductor _{L 1} is started injected in a state where the panel capacitor _{C p} in the Y electrode voltage _{V y} and the X electrode voltage _{V x} is maintained in each -V _s / 2 voltage, a ground line 0, the switching element _{Y r,} inductor _{L 1,} the route to the switching element _{Y g} (1 example of a first path), the current _{I L1} flowing to inductor _{L 1} is increased with a slope of _{V s} / 2L _1, energy ( (First energy) is conserved. That is, for example, if the mode 1 (M1) is sustained Delta] t ₁ hour, current _{I p1} flowing to inductor _{L 1} at the time the mode 1 (M1) end is as Equation (1) below.

Next, when mode 2 (M2: one example of the second stage, one example of the eleventh stage) starts, the switching element _Yg is cut off, and as shown in FIG. 4B, the ground line 0, the switching element _Yr , and the inductor A current path (an example of a second path) is formed in L ₁ , the panel capacitor C _p , the switching element X _g , and the power supply −Vs / 2, the panel capacitor _CP is charged, the voltage _Vy rises, and the inductor and L ₁ of the current increase rate is decreased, LC resonance occurs. The Y electrode voltage V _y of panel capacitor C _p by LC resonance increases, continues to increase until V _s / 2 to be clamped by the body diode of switch Y _s. Rate of increase affects the operating speed Y electrode voltage V _y, since the inductor L ₁ is proportional to the current supplied to the panel capacitor C _P, time according to the Y electrode voltage V _y increases to V _s / 2 ΔT _r It is determined by the current _{I p1} flowing to inductor _{L 1} at resonance. That is, the rise time [Delta] T _r of Y electrode voltage _{V y} as the following equation (2), the current _{I p1,} i.e., current injection time Delta] t ₁ of mode 1 (M1), therefore, cut off timing of the switching element _{Y g} Can be adjusted by

Mode 3: (M3 1 example of the third stage) starts, when the Y electrode voltage _{V y} of panel capacitor _{C p} is increased to _{V s} / 2, the Y electrode voltage _{V y} conducting switching element _{Y s} is V _s / 2. Then, as shown in FIG. 4C, the current _{I L1} flowing to inductor _{L 1} is the switching element _{Y r,} inductor _{L 1,} a path of the body diode of switch _{Y s} (1 example of the sixth path), -V _s / 2L ₁ slope decreases to zero amperes by. That is, the current _{I L1} flowing to inductor _{L 1} is recovered to the power source Vs / 2. That is, the energy remaining in the inductor L ₁ is recovered.

Figure 3 and mode 4, as shown in Figure 4D: If (M4 1 example of step 12) starts, the switching element Y _r is cut off after the current I _L1 flowing to inductor L ₁ becomes 0A. Since the switching elements Y _s and X _g are conducting, the path of the switching element Y _s , the panel capacitor C _p , and the switching element X _g (an example of a fifth path) causes the Y electrode voltage of the panel capacitor C _p to pass. V _y and the X electrode voltage _{V x} can continue to be maintained in each _{V s} / 2 and -V _s / 2 voltage. Y and X electrodes of the voltage difference V _y -V _x the required voltage to sustain the discharge sustain discharge. Therefore V _s voltage (hereinafter, sustain discharge voltage hereinafter) is generated. Incidentally, when the current I _L1 flowing to inductor L ₁ is the switching element Y _r even after becoming zero amperes is conducting, also blocked by the diode D _y1 as tends to flow the inductor current in the opposite direction I _{L1 =} 0A State continues.

Mode 5: Switching element _{Y f} is turned in (M5 fourth example of phase) the switching element _Y s, _{X g} is conductive. Then, the power source Vs / 2 as shown in FIG. 4E, (1 example of the third path) switching element _{Y s,} inductor _{L 1,} the switching element _{Y f,} a current path to a ground line 0 is formed, flowing to inductor _{L 1} current instead of the reverse, the amount increases per unit time becomes -V _s / 2L _1. That is, in mode 5 (M5), a Y electrode voltage _{V y} and the X electrode voltage _{V x} of panel capacitor _{C p} in each while maintaining the _{V s} / 2 and -V _s / 2, the mode 1 (M1) is injecting currents in opposite directions in the inductor L _1. That is, the energy (second energy) is stored in the inductor _{L 1.}

Mode 6 (M6: example of the fifth stage, one example of a 13 stage) When starts, the switching element _{Y s} is blocked as shown in FIG. 4F, the switching element _{X g,} panel capacitor _{C p,} inductor _{L 1} , The switching element Y _f , and a current path (an example of a fourth path) are formed in the ground line 0, and LC resonance occurs. The Y electrode voltage _{V y} of panel capacitor _{C p} by LC resonance is decreased, decreased by the body diode of switch _{X g} to -V _s / 2. However, the LC resonance is as if the mode 2 (M2), so generated in a state in which current of a constant amount of the inductor _{L 1} is flowing, the panel capacitor _{C p} Y electrode voltage _{V y} is -V _s / time [Delta] T _f according to reduced to 2 is determined by the current flowing through the inductor L ₁ at resonance. As described in mode 1 (M1), the current flowing through the inductor L ₁ at resonance is determined by the period Delta] t ₅ of mode 5 current in the inductor L ₁ is a time period that is injected (M5).

Next, the mode 7: In (M7 first example of six stages), the Y electrode voltage _{V y} of panel capacitor _{C p} in the preceding mode (M6) is reduced, attempts to change more negative than -V _s / 2 When, conducts the body diode of switch _{Y g,} Y electrode voltage _{V y} is maintained at -V _s / 2 is a mode 7 (M7). Then, as shown in FIG. 4G, the current _{I L1} flowing to inductor _{L 1} is the body diode of switch _{Y g,} inductor _{L 1,} but flows in the path of the switching element _{Y f} (1 example of the seventh path), the inductor because of the voltage applied to L _1, it reaches 0A changes in the slope of _{V s} / 2L _1. That is, the energy remaining in the inductor L ₁ is recovered.

As shown in FIG. 3 and FIG. 4H, Mode 8: In (M8 1 example of step 14), the switching element _{Y f} after current _{I L1} flowing to inductor _{L 1} becomes 0A is cut off. Then, the switching element _Y g, _{X g} is Y electrode voltage _{V y} and the X electrode voltage _{V x} of panel capacitor _{C p} since it is interrupted each continues to be maintained at -V _s / 2.

In the course of modes 1 to 8 (M1 to M8), the panel capacitor _{C p} of the voltage across _V y -V _x (hereinafter, referred to as panel voltages) is zero volts (12 voltage) from _{V s} (13 voltages) You can swing back to zero volts after increasing to zero volts. Then, as shown in FIG. 3, the switching elements _X s in mode _{9~16 (M9~M16), X g,} X r, X f , and the switching element _{Y s, Y g, Y r} , the operation of the _{Y f} is switching element _Y s in each mode 1~8 _(M1~M8), Y _g, a similar operation and Y r, _{Y f,} and the switching elements _{X s, X g, X r} , X f. Therefore, X electrode voltage _{V x} of panel capacitor _{C p} in modes 9~16 (M9~M16) has the same waveform as the Y electrode voltage _{V y} in the mode 1 to 8 (M1 to M8). Accordingly, the panel voltage _V y -V _x in modes 9 to 16 (M9～M16) swings between zero volts (12 voltages) from -V _s (13 voltage). The detailed description of the operation in the modes 9 to 16 (M9 to M16) of the sustain discharge circuit according to the first embodiment of the present invention is easily made by those skilled in the art through the description of the modes 1 to 8 (M1 to M8). It is omitted because it can be understood.

According to the first embodiment of the present invention, by adjusting the time Δt1 injecting a current in the inductor L ₁ in mode 1 (M1), by adjusting the rise time ΔTr of the panel voltage can be, by adjusting the same manner mode 5 (M5) in the time of injecting current into the inductor L ₁ .DELTA.t5, it is possible to adjust the fall time ΔTf the panel voltage. Incidentally, amount of current injected into the inductor _{L 1} in mode (M1) is preferably greater than the current inflow into the inductor _{L 1} in mode 5 (M5). In this case, the rise time of the panel voltage can be shortened and the fall time can be lengthened.

However, as shown in FIG. 5, the state of the discharge space between the X electrode and the Y electrode of panel capacitor C _p, i.e., the wall charge state is not uniform for all discharge cells, each wall voltage discharge cells Different. If the wall voltage is small as in the discharge cell 51 shown on the left side of FIG. 5, the wall voltage V _w1 is low, so the voltage for starting the discharge becomes high, and the wall charge becomes large as in the discharge cell 52 shown on the right side. In this case, since the wall voltage _Vw2 is high, the voltage for starting discharge becomes low. When high starting voltage is the wall voltage as the discharge cell 52 is low, the discharge during the ascent of the panel voltage V _y -V _x is also start. That is, the intermediate in the discharge mode 2 (M2) for the switching element Y _s is blocked it is also start, power from the inductor L ₁ without being supplied with electric power for maintaining the discharge from the power source Vs / 2 Must be supplied. The mode 3 (M3) at the start of the conducting switching element Y _s discharge occurs again. By generating the discharge twice, uniform light cannot be generated on the entire panel. Therefore, it is preferable to shorten the rise time [Delta] T _r of a heterogeneous panel voltage so no discharge is V _y -V _x.

There also, when the panel voltage V _y -V _x abruptly decreases, the movement of the space charge due to a rapid change in the electric field, generated self-erasing of wall charges, also the wall charge distribution becomes uneven with respect to the discharge cells . However, the longer the falling period of the panel voltage V _y -V _x, the wall voltage decreases by the recombination of the space charges, self-erasing does not occur. Therefore, it is preferable that the falling period [Delta] T _f of the panel voltage _V y -V _x longer than the rising period [Delta] T _r of the panel voltage _V y -V _x.

Therefore, the sustain discharge circuit shown in FIG. 1 shows a driving timing in the case where the falling period [Delta] T _f of the panel voltage _V y -V _x longer than the rising period [Delta] T _r of the panel voltage _V y -V _x in FIG. That is, in FIG. 6, the period Δt ₁ during which the current is injected into the inductor L ₁ in the mode 1 (M 1) is longer than the period Δt ₅ during which the current is injected into the inductor L ₁ in the mode 5 (M 5). Therefore, rise time [Delta] T _r of the panel voltage _{V y} -V _x becomes shorter than the fall time [Delta] T _f.

Next, a sustain discharge circuit of the scan / sustain driver 300 according to the second embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a schematic circuit diagram of a sustain discharge circuit according to the second embodiment. FIG. 8 is a drive timing diagram of the sustain discharge circuit according to the second embodiment, and FIGS. 9A to 9H are circuit diagrams showing current paths in each mode in the sustain discharge circuit according to the second embodiment.

In the first embodiment described above, as shown in FIGS. 3 and 6, in the mode 9 (M9), but so as to inject a current in the inductor L ₂ of the current flowing through the inductor L ₁ after recovering all not necessarily limited to this, even in either mode 7 (M7) and mode 8 (M8) as sustain discharge circuit according to the second embodiment described later, it is possible to inject a current in the inductor L _2. That is, the mode 9 (M9) state can be generated within the period of the mode 7 (M7) or the mode 8 (M8). In this way, the period in which the panel voltage V _y -V _x is maintained at zero volts can be shorter than the first and second embodiments.

In the first embodiment described above, the power source Vs / 2, respectively and _{V s} / 2 and -V _s / 2 the voltage supplied is -Vs / 2, the Y electrode voltage _{V y} and the X electrode voltage _{V x} Although the voltage V _s necessary to sustain the difference, not necessarily limited thereto, such as the sustain discharge circuit according to the second embodiment described later, Y and X electrodes in each second voltage, for example, the sustain discharge voltage it is also possible to apply the V _s and the first voltage (11 voltages) for example, a ground voltage 0V.

Hereinafter, the second embodiment will be specifically described. As shown in FIG. 7, the sustain discharge circuit according to the second embodiment differs from the first embodiment in that switches Y _s and X _s are connected to a power supply Vs for supplying a sustain discharge voltage V _s. , Switches Y _g , X _g are connected to ground line 0 which supplies a ground voltage of zero volts. _Further , capacitors C _yer1 and C _yer2 are connected in series between the power supply Vs and the ground line 0, and switches Y _r and Y _f are connected to a connection point of the capacitors C _yer1 and C _yer2 . Similarly, and capacitor _{C xer1, C xer2} is connected in series between the power source Vs and the ground line 0, switch _X r, _{X f} is connected to the connection point of the capacitor _{C xer1, C xer2.} Such capacitors C _yer1 , C _yer2 , C _xer1 , C _xer2 are _charged with V ₁ , V ₂ (corresponding to a third voltage), V ₃ , and V ₄ , respectively. Incidentally, for example, the Y _g, Y _s is first respectively, constitute another example of the second switching element, the Y _r, Y _f each third, constitute another example of the fourth switching element.

Here, it assumed to be V _s / 2 voltage V ₂ voltage and V ₄ voltage corresponding to half of the sustain discharge voltage Vs, Fig. 8, according to the second embodiment with reference to FIG. 9A~ view 9H The operation of the sustain discharge circuit will be described.

As shown in FIG. 8, Mode 1: In (M1 another embodiment of the first stage), the switching element _Y g, the switching element _{Y r} in a state in _{which X g} are turned conductive. Then, the capacitor _{C yermolayev yer-2} as shown in FIG. 9A, the switching element _{Y r,} (another example of the first path) inductor _{L 1,} the current path of the switching element _{Y g} is formed, the current flowing through the inductor _{L 1 I L1} increases in the slope of _{V s} / 2L _1. That is, the energy in the inductor L ₁ (first energy) is accumulated in a state mode 1 (M1) in which the the panel capacitor C _p Y electrode voltage V _y and the X electrode voltage V _x is maintained in each zero volts.

Mode 2 (M2: another example of the second stage, another example of the 11th stage), the switching element _{Y g} is turned off, the capacitor _{C yermolayev yer-2} as shown in FIG. 9B, the switching element _{Y r,} inductor _L 1, A current path (another example of the second path) is formed in the panel capacitor C _p , the switching element X _g , and the ground line 0, and LC resonance occurs. The LC is Y electrode voltage _{V y} of panel capacitor _{C p} by the resonance increases, which increases the switching element _{Y s} of the body diode to _{V s} voltage. However, the LC resonance is generated in a state in which a certain amount of current flows as in the first embodiment to the inductor L ₁ (state energy in the inductor is stored).

Mode 3: (M3 another example of the third stage), when Y electrode voltage _{V y} of panel capacitor _{C p} is increased to _{V s} voltage switching element _{Y s} is turned Y electrode voltage _{V y} is _{V s} voltage Is maintained. Then, the capacitor _{C Yer1} as shown in FIG. 9C, the switching element _{Y r,} inductor _{L 1,} the current I flowing in the inductor _{L 1} by (another example of the sixth path) route path of the body diode of switch _{Y s L1} is collected by the capacitor _Cyer1 .

As shown in FIG. 8 and FIG. 9D, Mode 4: (M4 another example of step 12), the switching element _{Y r} is cut off after the current _{I L1} flowing to inductor _{L 1} becomes 0A. Since the switching elements Y _s and X _g are conducting, the Y electrodes of the panel capacitor C _p are formed by the paths of the switching elements Y _s , the panel capacitors C _p and the switching elements X _g (another example of the fifth path). voltage _{V y} and the X electrode voltage _{V x} continues to be maintained in each _{V s} voltage and zero volts. Since the voltage difference V _y -V _x of Y and X electrodes becomes the sustain discharge voltage, the sustain discharge is generated.

In mode 5 (M5: another example of the fourth stage), the switching elements Y _s and X _g are in a conductive state and the switching element Y _f is in a conductive state. Then, the power supply as shown in FIG. 9E Vs, switching element _{Y s,} inductor _{L 1,} the switching element _{Y f,} a current path in the capacitor _{C yermolayev yer-2} (another example of the third path) is formed, the current flowing through the inductor _{L 1} decreases at a slope of -V _s / 2L _1. In mode 5 (M5), while keeping the Y electrode voltage _{V y} and the X electrode voltage _{V x} of panel capacitor _{C p} each _{V s} voltage and zero volts, the inductor in the opposite direction of the current of the mode 1 (M1) It is injected into the L _1. That is, energy (second energy) is stored in the inductor.

Mode 6 (M6: Another example of the fifth stage, another example of the 13th stage), the switching element _{Y s} is blocked switching element as shown in FIG. 9F _{X g,} panel capacitor _{C p,} inductor _{L 1} , The switching element Y _f , and the capacitor _Cyer2 , a current path (another example of the fourth path) is formed, and LC resonance occurs. Y electrode voltage V _y of panel capacitor C _p by LC resonance is reduced, but reduced to zero volts by the body diode of switch X _g. However, the LC resonance is generated in the mode 2 (the state in which energy is stored in the inductor) state a certain amount of current is flowing to inductor L ₁ as in the case of (M2).

Mode 7: In (M7 second another example of a 6 step), the Y electrode voltage V _y of panel capacitor C _p is decreased to zero volts, and conducts the switching element Y _g, maintained at the Y electrode voltage V _y is zero volts Is done. Then, as shown in FIG. 9G, current _{I L1} flowing in the inductor _{L 1} is the body diode of switch _{Y g,} inductor _{L 1,} the switching element _{Y f,} the path of the capacitor _{C yermolayev yer-2} (1 example of the seventh path) _And collected by the capacitor _Cyer2 .

As shown in FIG. 8 and FIG. 9H, Mode 8: In (M8 another example of step 14), the switching element _{Y f} is interrupted after the current _{I L1} flowing to inductor _{L 1} becomes 0A. Then, the switching element _Y g, since _{X g} is conductive, Y electrode voltage _{V y} and the X electrode voltage _{V x} of panel capacitor _{C p} is continuously maintained each zero volts.

Thus, in the second embodiment, as in the first embodiment, the mode 1 (M1) in the course of ~ mode 8 (M8), the panel voltage _V y -V _x is zero volts _{V s} You can swing between. Then, as shown in FIG. 9, the switching elements _X s in mode _{9~16 (M9~16), X g,} X r, X f , and the switching element _{Y s, Y g, Y r} , the operation of the _{Y f} is switching element _Y s in each mode 1~8 _(M1~M8), Y _g, a similar operation and Y r, _{Y f,} and the switching elements _{X s, X g, X r} , X f.

In such a second embodiment, by adjusting the voltage V ₂ charged in the capacitor C _{yermolayev yer-2,} can adjust the rise time and the fall time of the panel voltage. That is, in FIG. 9, switch _Y r, and duration of the mode 1 (M1) _{to Y g} is turned simultaneously, switch _Y s, by _{Y f} is to adjust the duration of the mode 5 (M5) which is cut off at the same time, the capacitor _Adjustment of the voltage level of _Cyer2 is possible.

Next, a method of adjusting the voltage level of the capacitor _Cyer2 will be described with reference to FIGS. FIGS. 10 to 12 are diagrams illustrating a discharge current and a charge current of the capacitor _Cyer2 in the sustain discharge circuit according to the second embodiment, respectively.

As shown in FIG. 10, when the period Δt ₁ of mode ₁ is equal to the period Δt ₅ of mode 5, the current discharged from the capacitor C _{yer2 in} mode 1 and the current charging the capacitor C _{yer 2 in} mode 5 are different. Be the same. Therefore, the voltages V ₁ and V ₂ across the capacitors C _yer2 and C _yer2 maintain the voltage V _s / 2.

In this case, when the magnitude of current I _L1 flowing to inductor L ₁ in mode 2, and mode 6, as shown in FIG. 8 is maximized, Y electrode voltage V _y of panel capacitor C _p is approximately V _s / It becomes two voltages.

On the other hand, as shown in FIG. 11, when the period Delta] t ₁ of mode 1 is shorter than the period Delta] t ₅ of mode 5, the discharge current of the capacitor _{C yermolayev yer-2} is smaller than the charging current of the capacitor _{C yermolayev yer-2.} Then, when it becomes an equilibrium state, the voltage across _{V 2} of capacitor _{C yermolayev yer-2} is to maintain the two ends voltages _{V 1} is greater than value of the capacitor _{C yer1.} That, _{V 2} voltage is greater than _{V s} / 2.

In this case, in the mode 2 (M2), the voltage _{V 2} applied to the resonance of the inductor _{L 1} and the panel capacitor _{C p} is greater than _{V s} / 2 voltage, the current _{I L1} flowing to inductor _{L 1} when the magnitude is maximized, Y electrode voltage V _y of panel capacitor C _p is a V _s / 2 greater than voltage. Therefore, when the elapsed slightly from the time when the magnitude of current I _L1 reaches a maximum, the Y electrode voltage V _y becomes V _s voltage rise time [Delta] T _r of the panel voltage is shorter.

On the other hand, as shown in FIG. 12, when the period Delta] t ₁ of mode 1 is longer than the period Delta] t ₅ of mode 5, the discharge current of the capacitor _{C yermolayev yer-2} is greater than the charging current of the capacitor _{C yermolayev yer-2.} Then, when an equilibrium state is _established , the voltage V ₂ across the capacitor C _yer2 maintains a value smaller than the voltage V ₁ across the capacitor C _yer1 . In other words, _{V 2} voltage is smaller than _{V s} / 2.

In this case, in the mode 2 (M2), the voltage _{V 2} applied to the resonance of the inductor _{L 1} and the panel capacitor _{C p} is less than _{V s} / 2 voltage, the current _{I L1} flowing to inductor _{L 1} when the magnitude is maximized, Y electrode voltage V _y of panel capacitor C _p is a V _s / 2 less than voltage. Therefore, when a lot of time elapsed from when the magnitude of current I _L1 reaches a maximum, the Y electrode voltage V _y becomes V _s voltage rise time [Delta] T _r of the panel voltage is increased.

Thus, in the second embodiment, by adjusting the duration of the mode 1 (M1) and Mode 5 (M2), may be other voltage not V _s / 2 voltage a voltage of the capacitor C _{yermolayev yer-2} . Thus, the rise time and the fall time of the panel voltage can be adjusted.

At this time, in the second embodiment, the current in mode 3 can be recovered by the power supply Vs by removing the capacitor _Cyer1 . Furthermore, it is also possible to connect the power supplies _{V 2} voltages instead of the capacitor _{C yermolayev yer-2.} In this case the V ₂ voltage is V _2/2 voltage, as described in the first embodiment, by adjusting the period of mode 1 and mode 5, to adjust the rise time and the fall time of the panel voltage It is also possible.

Then, it is also possible to connect the capacitor C _{yermolayev yer-2} instead of the ground line 0. In the sustain discharge circuit of FIG. 2 described above switch Y _r, the Y _f. Then, as described above, the rise time and the fall time of the panel voltage can be adjusted by adjusting the discharge current (mode 1) and the charge current (mode 2) of the capacitor _Cyer2 . In addition, a power supply for supplying the same voltage may be connected instead of the capacitor _Cyer2 .

Then, in the first and second embodiments it has been described a voltage applied to the Y electrode as Vs voltage and zero volts or V _s / 2 voltage and -V _s / 2 voltage. Two voltages V _h, the V _h -V _s may be applied to the Y electrode the difference between the two voltages is V _s voltage Unlike this.

Next, a sustain discharge circuit of the scan / sustain driver 300 according to the third embodiment of the present invention will be described in detail with reference to FIGS. FIG. 13 is a schematic circuit diagram of a sustain discharge circuit according to the third embodiment, and FIG. 14 is a drive timing diagram of the sustain discharge circuit according to the third embodiment.

As shown in FIG. 13, the sustain discharge circuit according to a third embodiment of the voltage -V _s / 2 - not used as a power source, except that supplied by using the capacitors C _1, C ₂ Is substantially the same as the sustain discharge circuit according to the first embodiment shown in FIG. The driving method according to the first embodiment can also be applied to the driving method of the sustain discharge circuit shown in FIG.

More specifically, the sustain discharge circuit according to the third embodiment further includes a switching element _{Y h, Y l, X h} , X l, the capacitors _C 1, _{C 2} and the diode _{D y3, D x3,} capacitor _{C 1} , the voltage of _{V s} / 2, respectively are charged to the _{C 2.} Switching element Y _h, Y _l are connected in series between the power source Vs / 2 and the ground line 0, between the switching element Y _h, a connection point Y _l and the ground line 0, the capacitor C ₁ and the diode _Dy3 are connected in series. Switching element _{Y s} is connected to the connection point of the switching element _Y h, _{Y l,} the switching element _{Y g} is connected to the connection point between the capacitor _{C 1} and diode _{D y3.} Similarly, the switching elements X _h, X _l are connected in series between the power source Vs / 2 and the ground line 0, is between the connection point and the ground line 0, the capacitor C ₂ and a diode D _x3 in series It is connected to. Switching elements _{X s} are connected to the connection point of the switching elements _X h, _{X l,} the switching device _{X g} is connected to the connection point between the capacitor _{C 2} and a diode _{D x3.}

Such operation of the third sustain discharge circuit according to an embodiment of the switching elements as shown in FIG. _{14 Y s, Y g, X} s, the time when _{the X g} operates each switching element _Y h, _{Y l} , _Xh , and _Xl operate at the same time except that they operate simultaneously. More particularly, supplies a switching element _Y s, the voltage of the _{Y h} power Vs / 2 to the panel capacitor _{C p} become simultaneously conductive _{V s} / 2. Similarly, the switching elements _X s, supplies power Vs / 2 voltage _{V s} / 2 and _{X h} conducts simultaneously the panel capacitor _{C p.} Also supplies the switching element _Y g, _{Y l} is a ground line is turned on at the same time 0, the switching element _{Y l,} capacitor _{C 1,} a voltage of -V _s / 2 to the panel capacitor _{C p} through a path of the switching element _{Y g} . Similarly the switching elements _X g, _{X l} is a ground line conducting simultaneously 0, the switching element _{X l,} capacitor _{C 1,} and supplies a voltage of -V _s / 2 to the panel capacitor _{C p} through a path of the switching device _{X g.}

According to the third embodiment, it is possible to supply V _s / 2 voltage and -V _s / 2 voltage to the panel capacitor C _p in the power supplies V _s / 2 voltage.

Next, a sustain discharge circuit of the scan / sustain driver 300 according to the fourth embodiment of the present invention will be described with reference to FIGS. FIG. 15 is a schematic circuit diagram of a sustain discharge circuit according to the fourth embodiment, and FIG. 16 is a drive timing diagram of the sustain discharge circuit according to the fourth embodiment.

In the first to third embodiment uses the same inductor L ₁ to rise and fall of the Y electrode voltage V _y, not necessarily limited thereto. In this regard, in the fourth embodiment uses a different rise and fall of the Y electrode voltage _{V y} inductor _{(L 11, L 12} in FIG. 15). When such two inductors are used, the step of injecting current into the inductors (M1 and M5 in FIG. 3) can be omitted. For example, the inductors L ₁₁ and L ₁₂ each constitute one example of first and second inductors.

Hereinafter, such a fourth embodiment will be specifically described. 15 shows, in the X electrode voltage is the stage of panel capacitor C _p is assumed to maintain zero volts, there is shown only the Y electrode portion of the sustain discharge circuit. The sustain discharge circuit according to the fourth embodiment is almost the same as the first embodiment except for the inductors L ₁₁ and L ₁₂ , the capacitor _Cyer , the power supply Vs, and the ground line 0.

More specifically, connected in series between the switching element Y _s, Y _g is a ground line 0 which corresponds to the signal lines (voltage 0 in this case) power source Vs and the eleventh voltage supplies 13 voltage e.g. V _s Have been.

The inductor _{L 11} is connected between the switching element _Y s, _{Y g} of connecting points and the switching element _{Y r,} inductor _{L 12} is connected between the switching element _Y s, _{Y g} of connecting points and the switching element _{Y f} Have been. A capacitor C _yer is connected between the connection point of the switching elements Y _r and Y _f and the ground line 0. Power source Vs is supplied to _{V s} voltage and _{V s} / 2 voltage is charged in the capacitor _{C yer.} That is, the power source Vs and the ground line 0, Y electrode voltage V _y swings between V _s is a thirteenth voltage from zero volts twelfth voltage different from the first embodiment.

As shown in FIG. 15, the mode 1 (M1) in conducting the switching element _{Y r,} capacitor _{C yer,} switching element _{Y r,} inductor _{L 11,} LC resonance with the panel capacitor _{C p} path (first resonance path) Occurs. This LC resonance, as shown in FIG. 16, the panel voltage _{V p} becomes to increase, the current _{I L11} inductor _{L 11} forms a half period of the sine wave (0 degrees to 180 degrees). In mode 2 (M2), when the Y electrode voltage _{V y} has increased to _{V s} voltage switching element Y switching element _{Y r} is turned off is turned on, the Y electrode voltage _{V y} is maintained at _{V s} . That is, the panel performs sustain discharge in mode 2 (M2).

Then, in the mode 3 (M3), switching element _{Y f} switching element _{Y s} is turned off is turned on, the panel capacitor _{C p,} inductor _{L 12,} the switching element _{Y f,} the path of the capacitor _{C yer} (second LC resonance occurs in the resonance path). The panel voltage _{V p} by the resonance is reduced, the current _{I L12} of the inductor _{L 12} forms a cycle (360 degrees 180 degrees) the second half of the sine wave. When the mode 4 (M4) in the panel voltage V _p is reduced to zero volts, the switching element Y _f is the switching element Y _g off is turned on, Y electrode voltage V _y is maintained at zero volts.

Then, to swing between the X electrode voltage _{V x} to zero volts through a process corresponding to the mode 1 to 4 (M1 to M4) while maintaining the Y electrode voltage _{V y} to zero volts _{V s} voltage. Thus it is possible to supply a voltage V _s necessary to maintain discharge to the panel.

Below, as shown in Equation (3) and (4), rise time [Delta] T _r and fall time [Delta] T _f of the Y electrode voltage _{V y} are each a function of the inductance _{L 11, L 12} of the inductor _{L 11, L 12} since, by adjusting the inductance _{L 11, L 12,} it is possible to adjust the rise time [Delta] T _r and fall time [Delta] T _f of the panel voltage _{V y.} At this time, by increasing the inductance L ₁₂ to reduce inductance L ₁₁ as described above, it is preferable that the rise time [Delta] T _r of the panel voltage V _y shortened so as long a fall time [Delta] T _f.

In the fourth embodiment, the power supplies Vs / 2 and -Vs / 2 can be used as in the first embodiment. That is, it is possible to respectively supply Vs / 2, concatenates the -Vs / 2 to the switching element _Y s, _{Y g,} connects the ground line 0 instead of the capacitor _{C er} to the connection point of the switching element _Y r, _{Y f} . In this way, it is possible to swing between the Y electrode voltage V _y of panel capacitor C _p as in the first embodiment from -V _s / 2 voltage V _s / 2 voltage. When Y electrode voltage _{V y} is _{V s} / 2 voltage, it is possible to maintain the X electrode voltage _{V x} to -V _s / 2, to supply voltage _{V s} necessary to maintain the discharge in the panel.

According to the present invention, as described in the first to fourth embodiments, the rise time and the fall time of the panel voltage can be adjusted. In particular, uniform discharge is possible by making the rise time of the panel voltage rapid and preventing discharge from occurring twice during the rise of the panel voltage. Further, by making the falling time of the panel voltage longer than the rising time, it is possible to prevent the self-erasure of the wall charges from occurring and to make the wall charge distribution between the discharge cells uniform.

Although the preferred embodiments of the present invention have been described with reference to the accompanying drawings, it is needless to say that the present invention is not limited to the examples. It is clear that a person skilled in the art can conceive various changes or modifications within the scope of the claims, and these naturally belong to the technical scope of the present invention. I understand.

For example, in the above-described embodiment, the case has been described where the third voltage is a voltage intermediate between the first voltage and the second voltage. However, the third voltage is an intermediate voltage between the first voltage and the second voltage. The third voltage may be a voltage between the first voltage and the second voltage, and may be a voltage between the voltage and the second voltage.

The present invention is applicable to a driving device and a driving method for driving a plasma display panel.

1 is a schematic block diagram of a plasma display panel according to the present invention. FIG. 2 is a schematic circuit diagram of a sustain discharge circuit according to the first embodiment of the present invention. FIG. 3 is a diagram showing an example of a drive timing of a sustain discharge circuit according to the same embodiment. FIG. 3 is a circuit diagram showing a current path in mode 1 in the sustain discharge circuit according to the same embodiment. FIG. 3 is a circuit diagram showing a current path in mode 2 in the sustain discharge circuit according to the same embodiment. FIG. 3 is a circuit diagram showing a current path in mode 3 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 4 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 5 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 6 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 7 in the sustain discharge circuit according to the same embodiment. FIG. 9 is a circuit diagram showing a current path in mode 8 in the sustain discharge circuit according to the same embodiment. FIG. 3 is a diagram showing a state of wall charges in a discharge cell in the same embodiment. FIG. 4 is a diagram showing another example of the drive timing of the sustain discharge circuit according to the same embodiment. FIG. 6 is a schematic circuit diagram of a sustain discharge circuit according to a second embodiment of the present invention. FIG. 4 is a drive timing chart of the sustain discharge circuit according to the same embodiment. FIG. 3 is a circuit diagram showing a current path in mode 1 in the sustain discharge circuit according to the first embodiment. FIG. 3 is a circuit diagram showing a current path in mode 2 in the sustain discharge circuit according to the same embodiment. FIG. 3 is a circuit diagram showing a current path in mode 3 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 4 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 5 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 6 in the sustain discharge circuit according to the same embodiment. FIG. 4 is a circuit diagram showing a current path in mode 7 in the sustain discharge circuit according to the same embodiment. FIG. 9 is a circuit diagram showing a current path in mode 8 in the sustain discharge circuit according to the same embodiment. FIG. 3 is a diagram showing a discharge current and a charge current of a capacitor in the sustain discharge circuit according to the same embodiment. FIG. 3 is a diagram showing a discharge current and a charge current of a capacitor in the sustain discharge circuit according to the same embodiment. FIG. 3 is a diagram showing a discharge current and a charge current of a capacitor in the sustain discharge circuit according to the same embodiment. FIG. 9 is a schematic circuit diagram of a sustain discharge circuit according to a third embodiment of the present invention. FIG. 4 is a drive timing chart of the sustain discharge circuit according to the same embodiment. FIG. 11 is a schematic circuit diagram of a sustain discharge circuit according to a fourth embodiment of the present invention. FIG. 4 is a drive timing chart of the sustain discharge circuit according to the same embodiment.

Explanation of reference numerals

100 plasma panel 200 address driver 300 scan and sustain driver 400 controller 310 Y electrode driver 320 X electrode driver 330 Y electrode power recovery section 340 X electrode power recovery section _{Y s, Y g, X s} , X g switching element _{Y r, Y f, X r} , X f switching element _{Y h, Y l, X h} , X l switching elements _L 1, _{L 2} inductor _{C p} panel capacitor _{C yer1, C yer2} capacitor _{C xer1, C xer2} capacitor V _y Y electrode voltage _{V x} X electrode voltage Vs / 2 + power -Vs / 2 - power 0 ground line _{D y1, D y2, D x1} diode _{D x2, D y3, D x3} diode _V y -V _x panel voltage

Claims (34)

A method for driving a plasma display panel in which a panel capacitor is formed between first and second electrodes, comprising:
While the voltages of the first and second electrodes are each maintained at the first voltage, a current in a first direction is injected into an inductor electrically connected to the first electrode to store a first energy. One stage,
While the voltage of the second electrode is maintained at the first voltage, the voltage of the first electrode is changed to the second voltage using the resonance between the inductor and the panel capacitor and the first energy. The second stage,
Recovering the energy remaining in the inductor while maintaining the voltages of the first and second electrodes at the second and first voltages, respectively;
A method for driving a plasma display panel, comprising: While maintaining the voltages of the first and second electrodes at the second and first voltages, respectively, a current in a second direction opposite to the first direction is injected into the inductor to store second energy. The fourth stage,
While the voltage of the second electrode is maintained at the first voltage, the voltage of the first electrode is changed to the first voltage using the resonance between the inductor and the panel capacitor and the second energy. The fifth stage,
A sixth step of recovering energy remaining in the inductor while maintaining the voltages of the first and second electrodes at the first voltage, respectively;
The method of driving a plasma display panel according to claim 1, further comprising: 3. The method of driving a plasma display panel according to claim 1, wherein the difference between the first voltage and the second voltage is a sustain discharge voltage. 3. The method according to claim 2, wherein the amount of current injected into the inductor in the first direction in the first stage is greater than the amount of current injected into the inductor in the second direction in the fourth stage. A method for driving a plasma display panel. 3. The plasma display panel according to claim 2, wherein the time for changing the voltage of the first electrode in the second step is shorter than the time for changing the voltage of the first electrode in the fifth step. Drive method. The first and second voltages are supplied by first and second signal lines, respectively.
The first step is a path formed between a third signal line for supplying a third voltage having a magnitude between the first and second voltages, the inductor, and the first signal line, and a path formed between the inductor and the first signal line. Inject current in one direction,
3. The method of claim 2, wherein in the fourth step, the current in the second direction is injected into the inductor through a path formed between the second signal line, the inductor, and the third signal line. Driving method of a plasma display panel. The second step generates resonance in a path formed in the third signal line, the inductor, and the panel capacitor,
7. The method of claim 6, wherein in the fifth step, resonance is generated in a path formed by the panel capacitor, the inductor, and the third signal line. 3. The driving method of claim 2, wherein a resonance is generated by a voltage difference between a third voltage between the first voltage and the second voltage and a voltage of the first electrode. Method. 9. The method as claimed in claim 8, wherein the third voltage is a voltage corresponding to an intermediate value between the first voltage and the second voltage. The third voltage is provided by a capacitor;
The current in the first direction is a current discharged from the capacitor, the current in the second direction is a current for charging the capacitor, and the energy discharged from the capacitor and the energy for charging the capacitor are substantially equal. 10. The method according to claim 9, wherein the driving method is the same as the driving method. 9. The driving method of claim 8, wherein the third voltage is a voltage between the first voltage and the second voltage and a voltage between the second voltage and the third voltage. Method. The third voltage is provided by a capacitor;
The current in the first direction is a current discharged from the capacitor, the current in the second direction is a current for charging the capacitor, and the energy discharged from the capacitor is smaller than the energy for charging the capacitor. The method of driving a plasma display panel according to claim 11, wherein: A method for driving a plasma display panel in which a panel capacitor is formed between first and second electrodes, comprising:
While the voltage of the second electrode is maintained at the first voltage, the voltage of the first electrode is reduced to the first voltage by using resonance between the first inductor electrically connected to the first electrode and the panel capacitor. An eleventh step of changing to two voltages;
A twelfth step of maintaining the voltages of the first and second electrodes at the second and first voltages, respectively;
While maintaining the voltage of the second electrode at the first voltage, the voltage of the second electrode is changed using resonance between a second inductor electrically connected to the first electrode and the panel capacitor. A thirteenth step of changing to the first voltage;
A fourteenth step of maintaining the voltages of the first and second electrodes at the first voltage, respectively;
A method for driving a plasma display panel, comprising: 14. The method of claim 13, wherein the first inductor has a smaller inductance than the second inductor. 15. The method according to claim 13, wherein the difference between the first voltage and the second voltage is a sustain discharge voltage. In the eleventh step, resonance is generated in a signal line for supplying a third voltage having a magnitude between the first and second voltages, a path formed in the first inductor and the panel capacitor,
15. The method of claim 13, wherein in the thirteenth step, resonance occurs in a path formed between the panel capacitor, the second inductor, and the signal line. An apparatus for driving a plasma display panel having a panel capacitor formed between first and second electrodes, comprising:
An inductor electrically connected to the first electrode;
A signal line for supplying a third voltage having a magnitude between the first and second voltages, the inductor, and the first voltage while the voltages of the first and second electrodes are maintained at the first voltage, respectively; A first path formed in a first power supply that supplies a current in a first direction to the inductor;
The voltage of the second electrode is maintained at the first voltage, and while the current in the first direction flows through the inductor, LC resonance is generated in the signal line, the inductor, and the panel capacitor, and A second path for changing the voltage of the electrode from the first voltage to the second voltage;
While the voltages of the first and second electrodes are maintained at the second and first voltages, respectively, a second power supply for supplying the second voltage, the inductor, and the signal line are formed. A third path through which a current in a second direction opposite to the first direction is injected;
While the voltage of the second electrode is maintained at the first voltage and the current in the second direction flows through the inductor, LC resonance occurs in the panel capacitor, the inductor, and the signal line, and A fourth path for changing the voltage of the electrode from the second voltage to the first voltage;
A driving device for a plasma display panel, including: 18. The apparatus of claim 17, wherein a difference between the first voltage and the second voltage is a sustain discharge voltage. 19. The apparatus according to claim 17, wherein the amount of current injected into the inductor in the first direction is greater than the amount of current injected into the inductor in the second direction. The time during which the voltage of the first electrode is changed from the first voltage to the second voltage by the second path is the time when the voltage of the first electrode is changed from the second voltage to the first voltage by the fourth path. 19. The driving apparatus of claim 17, wherein the change time is shorter than the change time. 19. The driving apparatus of claim 17, further comprising a capacitor for charging the third voltage. 22. The driving apparatus of claim 21, wherein the third voltage is a voltage corresponding to an intermediate between the first voltage and the second voltage. The driving method of claim 21, wherein the third voltage is a voltage between the first voltage and the second voltage and the second voltage. apparatus. 22. The plasma of claim 21, wherein energy discharged from the capacitor by the current in the first direction is substantially the same as energy charged to the capacitor by the current in the second direction. Display panel drive. 22. The apparatus of claim 21, wherein energy discharged from the capacitor by the current in the first direction is smaller than energy charged to the capacitor by the current in the second direction. . After the voltage of the first electrode is changed to the second voltage, a fifth path for electrically connecting the first electrode to the second power source to maintain the voltage of the first electrode at the second voltage. The driving apparatus of claim 17, further comprising: A sixth path formed in the inductor and the second power supply for recovering the current in the first direction flowing through the inductor after the voltage of the first electrode is changed to the second voltage;
After the voltage of the first electrode is changed to the first voltage, a seventh path formed in the inductor and the signal line for collecting the current in the second direction flowing through the inductor;
The driving apparatus of claim 17, further comprising: 19. The driving apparatus of claim 17, wherein the second electrode is electrically connected to the first power source and is maintained at the first voltage. A first switching device connected between the first power source and the first electrode;
A second switching device connected between the second power source and the first electrode;
A third switching element connected in parallel between the inductor and the signal line;
The first path is formed by turning on the first and third switching elements and turning off the second and fourth switching elements.
The second path is formed by turning on the third switching element and turning off the first, second, and fourth switching elements.
The third path is formed by turning on the second and fourth switching elements and turning off the first and third switching elements.
19. The driving apparatus of claim 17, wherein the fourth path is formed by turning on the fourth switching element and turning off the first to third switching elements. . 19. The plasma display panel according to claim 17, wherein the first voltage has the same magnitude as the second voltage and has the opposite sign, and the signal line is connected to a ground line. Drive. The first voltage is a ground voltage, the third voltage is a voltage corresponding to a half of the second voltage, and the signal line is connected to a capacitor charging the third voltage. 19. The driving device for a plasma display panel according to claim 17, wherein: An apparatus for driving a plasma display panel having a panel capacitor formed between first and second electrodes, comprising:
First and second inductors respectively electrically connected to the first electrode;
When the voltage of the second electrode is maintained at the first voltage, resonance occurs between the first inductor and the panel capacitor, and the voltage of the first electrode is changed to the second voltage. Resonance path,
When the voltage of the second electrode is maintained at the first voltage, resonance occurs between the second inductor and the panel capacitor, and the voltage of the first electrode is changed to the first voltage. And a second resonance path,
The driving device of a plasma display panel, wherein the first inductor has an inductance smaller than the second inductor. A method for driving a plasma display panel in which a panel capacitor is formed between first and second electrodes, comprising:
Charging the panel capacitor from a twelfth voltage to a thirteenth voltage while the voltage of the second electrode is maintained at an eleventh voltage;
Discharging the panel capacitor from the thirteenth voltage to the twelfth voltage while the voltage of the second electrode is maintained at the eleventh voltage;
Including
A method for driving a plasma display panel, wherein a time for charging the panel capacitor is shorter than a time for discharging the panel capacitor. A method for driving a plasma display panel in which a panel capacitor is formed between first and second electrodes, comprising:
Storing first energy in an inductor electrically connected between the capacitor charging a predetermined voltage and the panel capacitor;
Charging the panel capacitor through the inductor in which the first energy is stored;
Storing a second energy in the inductor;
Discharging the panel capacitor through the inductor in which the second energy is stored,
The driving method of a plasma display panel, wherein the predetermined voltage is adjusted according to an amount of the first energy and the second energy.

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